CN2702502Y - A ferromagnetic resonance diagnostic eliminator of voltage transformer - Google Patents
A ferromagnetic resonance diagnostic eliminator of voltage transformer Download PDFInfo
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- CN2702502Y CN2702502Y CN 200420005829 CN200420005829U CN2702502Y CN 2702502 Y CN2702502 Y CN 2702502Y CN 200420005829 CN200420005829 CN 200420005829 CN 200420005829 U CN200420005829 U CN 200420005829U CN 2702502 Y CN2702502 Y CN 2702502Y
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Abstract
The utility model provides a ferromagnetic resonance diagnostic eliminator of a voltage transformer, belongs to the control technical field, and is used for providing a device that can accurately diagnose ferromagnetic resonance and can carry out eliminating resonance. The ferromagnetic resonance diagnostic eliminator of a voltage transformer is composed of a central processing unit, an analogue quantity input unit, an eliminating resonance and output unit and human machine interface unit. The input end of the analogue quantity input unit is connected with the triangle voltage of the opening of the voltage mutual inductor and A, B and C three-phase voltages, and the output end of the analogue quantity input unit is connected with the input end of the central processing unit. The output end of the central processing unit is connected with the input end of the output unit, and the human machine interface unit is connected with the central processing unit. In the utility model, the central processing unit can diagnose accurately the ferromagnetic resonance and trigger an eliminator to rightly operate by checking and processing the triangle voltage of the opening of the voltage mutual inductor and the variable of the system A, B and C three-phase voltages introduced, and the ferromagnetic resonance diagnostic eliminator of the voltage transformer overcomes the defects of the existing mistaken operation, rejective operation, etc.
Description
Technical field:
The utility model relates to a kind of device that is used to eliminate the ferro resonance fault of instrument transformer, belongs to the control technology field.
Background technology:
Voltage transformer is an equipment commonly used in the electric power system, and the capacitance parameter of it and system forms the oscillation circuit of many complexity, because the nonlinear characteristic of electromagnetic potential transformer when satisfying certain condition, just might excite ferro-resonance over-voltage.The frequency of ferro resonance can be first-harmonic, also can be high order harmonic component (being generally 3 frequencys multiplication) or subharmonic (being generally 3 frequency divisions, 2 frequency divisions etc.).When the electric power system generation ferro resonance at instrument transformer place, often cause voltage transformer to burn or explode, cause serious accident.For this reason, traditional solution is that serial connection bulb or resistance are decayed on instrument transformer open delta winding.This method is that a complicated problems has been carried out " packing " simply, so that can't make diagnosis accurately at particular problem, can not tackle the problem at its root.
For this reason, a kind of analog harmonic elimination apparatus arises at the historic moment, and it can eliminate the ferro resonance of a certain characteristic frequency, yet but often because of the arc grounding misoperation.Subsequently, people propose a kind of harmonic elimination method of microcomputer-based intelligentization again, and so the foundation of its judgement is still the numerical value of voltage transformer open delta voltage.During voltage transformer generation ferro resonance, it only is one of fault feature that voltage appears in open delta, when high-pressure side fuse blows or generation systems resonance take place for system's generation single-phase earthing, voltage transformer, open delta all voltage will occur, and this moment, this harmonic elimination apparatus as criterion inevitably also misoperation, false alarm will take place.
In addition,, cause the diversity of resonance frequency, show as resonance, industrial frequency resonance, the frequency tripling resonance of three frequency division resonance, two divided-frequency and near frequency thereof owing to the complexity of the resonant tank and the resonance origin cause of formation, or the like.And common harmonic elimination apparatus only can be eliminated the resonance of a certain frequency and can not eliminate the resonance of various frequencies fully, so that produces malfunction or tripping.
Summary of the invention
Provide a kind of thereby the utility model is used to overcome the defective that traditional resonance diagnosis is easy to report by mistake and can accurately diagnose the diagnosis of voltage transformer ferro resonance and the cancellation element that can reliably carry out harmonic elimination ferro resonance.
The technical scheme that addresses the above problem is:
A kind of voltage transformer ferro resonance diagnosis cancellation element, it is made up of with output unit 3, man-machine interface unit 4 CPU 1, analog input unit 2, harmonic elimination, the input termination voltage transformer open delta voltage of analog input unit 2 and A, B, C three-phase voltage, the input of its output termination CPU 1, the output termination harmonic elimination of CPU 1 and the input of output unit 3, man-machine interface unit 4 is connected with CPU 1.
Above-mentioned voltage transformer ferro resonance diagnosis cancellation element, described CPU 1 is by central processor CPU, A/D converter U11, memory U10, PSD chip U4 forms, the AD0 of CPU～AD15 port by bus respectively with AD0～AD15 port of PSD chip U4, the D0 of memory U10～D7 port, A8～A14 port, the D0 of A/D converter U11～D7 port is connected, CPU /RD, / WR port meets the CNTL0 of PSD chip U4 respectively, the CNTL1 port, the WE of memory U10, the OE port, A/D converter U11 /WR, / RD port, the P1.5 port of CPU connects A/D converter U11's/the INT port, the HSO.1 of CPU～HSO.3 port connects harmonic elimination and output unit 3, the PG0 of PSD chip U4～PG7 port is by A0～A7 port of bus interface memory U10, PF0～PF7 port, PC0～PC4 port and PB0～PB4 port is respectively by bus interface man-machine interface unit 4, the PB6 of PSD chip U4, the PB7 port is the CS1 port of connected storage U10 respectively, A/D converter /the CS port, the CH0 of A/D converter U11～CH3 port connects 4 outputs of analog input unit 2 respectively.
Above-mentioned voltage transformer ferro resonance diagnosis cancellation element, described analog input unit 2 is made up of four identical circuit, each circuit is made up of voltage transformer, transport and placing device again, respectively connection opening three angle voltages and A, B, C three-phase voltage of the input of voltage transformer wherein, the output termination transport and placing device of voltage transformer, transport and placing device and resistance, electric capacity are connected into the first-order filtering circuit, and the output of transport and placing device connects the signal input part of A/D converter.
Above-mentioned voltage transformer ferro resonance diagnosis cancellation element, described harmonic elimination and output unit 3 are made up of inverter U2, solid-state relay U3, integrated alarm relay K A1, plant failure alarm relay KA2, three inputs of inverter U2 are connected with HSO.1～HSO.3 port of the CPU of CPU 1 respectively, and its three outputs are connected with VCC port, integrated alarm relay K A1 and the control coil of plant failure alarm relay KA2 of solid-state relay U3 respectively.
Above-mentioned voltage transformer ferro resonance diagnosis cancellation element, described man-machine interface unit 4 is made up of display chip U16, key circuit, indicator light circuit, and the signal input part of display chip U16 is connected with PF0～PF7 port, the PC0～PC4 port of PSD chip U4 in the CPU 1; Each key circuit is by button S1, resistance R 1, inverter U5 form, button be connected between power supply VCC and the ground after resistance is connected, its serial connection point connects the input of inverter, output is received the PB0～PB4 port of PSD chip U4 in the CPU 1 through bus, indicator light circuit is composed in series by LED 1, resistance R 6, a termination power VCC of sequential circuit, and the other end is through the U4PA1～PA7 port of bus interface PSD chip.
Adopt the voltage transformer ferro resonance diagnosis cancellation element of this structure, CPU is by detecting and handle the voltage transformer open delta voltage of introducing and A, the B of system, the variable of C three-phase voltage, greatly enriched the criterion of diagnosis, can make accurate diagnosis to ferro resonance, and trigger the harmonic elimination apparatus correct operation, overcome defectives such as the malfunction that in the past existed or tripping.
Description of drawings
Fig. 1 is an electric theory diagram of the present utility model;
Fig. 2 is circuit theory diagrams.
Embodiment
As we can see from the figure, the utility model is made up of with output unit 3, man-machine interface unit 4 CPU 1, analog input unit 2, harmonic elimination.
CPU 1 is made up of central processing unit (CPU) 80C196, PSD935 chip, memory U10 62256, A/D converter U11 MAX197.Central processing unit is the core of device, and it is connected with PSD935 chip, memory U1062256, A/D converter U11MAX197 by bus, each cell operation of control device.The FLASH ROM of band 4Mbit in the PSD935 chip, 64KRAM can be used for producing the GPLD of 24 tunnel outputs of external chip selection, control signal or logic function, is used for satisfying the requirement of stored program, data, peripheral interface expansion.Memory U1062256 is used for store sample data and participate in to calculate intermediate variable.A/D converter U11MAX197 is program-controlled 12 the A/D sampling systems of multrirange, and 8 analog input channels are provided.4 analog quantitys of analog input unit 2 input of this device are defined as open delta, A, B, C three-phase respectively, and totally 4 the tunnel, be connected with 16～19 pin of A/D converter U11MAX197.
Analog input unit 2 is made up of voltage transformer, transport and placing device U12～U15, resistance R 13～R16, capacitor C 1～C4.Transport and placing device U12～U15 adopts the OPO7 model, forms 4 road first-order filtering circuit with resistance, electric capacity respectively, its input termination voltage transformer, corresponding open delta and A, B, C three-phase voltage respectively.The signal of on-the-spot PT is diminished voltage transformer according to a certain percentage after filter circuit is sent into the input port of the A/D converter MAX197 of this device.
Harmonic elimination and output unit 3 are made up of inverter U2, solid-state relay U3, integrated alarm relay K A1, plant failure alarm relay KA2, and the model of inverter and solid-state relay adopts 74LS04 and SSR.1,3,5 pin of inverter 74LS04 are connected with 29,34,35 pin of CPU 80C196 respectively, and 2,4,6 pin of inverter 74LS04 are connected with 1 pin of solid-state relay SSR, integrated alarm relay K A1, plant failure alarm relay KA2 respectively.When device detects resonance, start solid-state relay SSR harmonic elimination, simultaneously the closed indication mechanism ferro resonance of the normal opened contact fault of integrated alarm relay K A1.When self-check of device is found faults itself, the normal opened contact closure of fault alarm relay K A2.
Man-machine interface unit 4 is made up of display chip U16, key circuit, indicator light circuit.Display chip U16 adopts graphical dots configuration liquid crystal chip, model is 12864A, its gating signal is provided by the decoding circuit of CPU 80C196 control PSD935 chip, control signal and data/address bus are latched by the universaling I/O port of CPU by the PSD935 chip and provide, and promptly 41～45 pin of PSD935 chip, 31～38 pin connect 4,5,6,15,16 pin and 7～14 pin of liquid crystal chip 12864A respectively.Key circuit adopts 5 road button S1～S5, and each road is connected between power supply VCC and the ground respectively with after resistance R 1～R5 connects, and output meets inverter U5～U9 respectively, and button and inverter adopt 12 * 12 buttons and 74HC14 inverter respectively.The indication level of button is sent into the universaling I/O port of PSD935 chip after via the anti-phase processing of one-level inverter 74HC14, i.e. 61～65 pin of PSD935 chip, and CPU 80C196 only need read this mouthful when detecting button data get final product.Indicator light circuit adopts 7 road LEDs, 1～LED7, they meet power supply VCC respectively with after resistance R 6～R12 connects, the output of light-emitting diode is by bus interface PSD935 chip, the data of indicator light are latched by the universaling I/O port of CPU 80C196 by the PSD935 chip and provide, i.e. 51～58 pin of PSD935 chip.
The course of work of the present utility model is as follows:
1. at first carry out self check after this device powers on.If fault is arranged, fault message is outputed to input 7～14 pin of liquid crystal chip 12864A by 31～38 pin of PSD935, the brilliant chip 12864A of feed flow shows fault message, and 52～58 pin by the PSD935 chip output to LED 1～LED7, light " fault " indicator light.Low level of high-speed output end 34 pin of CPU 80C196 output simultaneously to 3 pin of the inverter 74LS04 of harmonic elimination and output unit are exported 1 pin of high level to plant failure alarm relay KA2 by 4 pin of inverter 74LS04 after anti-phase the driving,, drive the actuating of relay.This device will quit work this moment, up to fault is got rid of.
2. this device detects key information in real time.When key is pressed, the indication level step-down of respective keys, handle 61～65 pin of sending into the PSD935 chip through inverter 74HC14 again, CPU detects the level of these pins, if high level illustrates that then corresponding key is pressed, carrying out the software delay button when discovery has key to press earlier disappears and trembles processing, and then read button data, after confirming have key to press, it is that He Jian presses that CPU judges, operate accordingly then: change parameter, check information etc., finish by software.
3. A, B, C three-phase voltage and open delta voltage are gathered and calculated to this device in real time.The voltage signal of on-the-spot voltage transformer is received the input of this device voltage transformer pt Uo1, PTUo2, PTUo3, PTUo4, outputing to behind its secondary through the voltage transformer conversion is the tiny signal that can be gathered by A/D converter U11MAX197, this signal is through delivering to input 3 pin of corresponding operational amplifier OP07 behind the capacitance resistance ware, capacitance resistance ware and OP07 constitute the first-order filtering circuit jointly, send into 16～19 pin of A/D converter U11MAX197 after the filtering from output 6 pin of operational amplifier OP07.CPU is by the working method of address wire 45～60 foot control system A/D converter U11MAX197, after in A/D converter U11MAX197, writing control command, conversion begins immediately, A/D converter was delivered to 30 pin of CPU after conversion finished from the low level interrupt signal of a standard of 24 pin output, CPU carries out the Interrupt Process subprogram after by this signal interruption, promptly gathers the voltage data subprogram.Calculating voltage value after collection finishes.If open delta voltage is less than harmonic elimination voltage starting value, judge then whether A, B, C three-phase voltage break, as broken string, then think the low-pressure side broken string, fault message is outputed to input 7～14 pin of liquid crystal chip 12864A by 31～38 pin of PSD935 chip, the brilliant chip of feed flow shows fault message, and 52～58 pin by the PSD935 chip output to LED 1～LED7, light " broken string " indicator light.Low level of high-speed output end 29 pin output of CPU 80C196 to 5 pin of inverter 74LS04 are exported high level to 1 pin that installs integrated alarm relay K A1 by 6 pin of 74LS04 after anti-phase the driving, drive the actuating of relay, make it the normal opened contact closure, by 11～19 pin of data/address bus 53～60 pin output fault data, fault message is stored simultaneously to memory U10.If open delta voltage is greater than harmonic elimination voltage starting value, utilize A at once, B, the negative sequence voltage value of C three-phase voltage computing system,, the negative sequence voltage value thinks the high-pressure side broken string if surpassing certain value, with the brilliant demonstration of fault message liquor charging, light " broken string " indicator light, the high speed output line of CPU is through the actuating coil of one-level inverter drive integrated alarm relay K A1 simultaneously, make it the normal opened contact closure, otherwise judge whether to be single-phase earthing again, if single-phase earthing, the brilliant chip of fault message liquor charging is shown, light " ground connection " indicator light, the high speed output line of CPU makes it the normal opened contact closure through the actuating coil of one-level inverter drive integrated alarm relay K A1 simultaneously.After being judged as resonance, low level of high-speed output end 35 pin output of CPU 80C196 to 1 pin of inverter 74LS04 is exported 1 pin of high level to solid-state relay SSR by 2 pin of 74LS04 after anti-phase the driving, driving solid relay SSR action, the ferro resonance of system is eliminated, simultaneously fault message is sent that demonstrations, " resonance " indicator light are lighted, integrated alarm relay K A1 moves.
Claims (5)
1. a voltage transformer ferro resonance is diagnosed cancellation element, it is characterized in that: it is made up of CPU [1], analog input unit [2], harmonic elimination and output unit [3], man-machine interface unit [4], the input termination voltage transformer open delta voltage of analog input unit [2] and A, B, C three-phase voltage, the input of its output termination CPU [1], the input of the output termination harmonic elimination of CPU [1] and output unit [3], man-machine interface unit [4] are connected with CPU [1].
2. according to the described voltage transformer ferro resonance diagnosis of claim 1 cancellation element, it is characterized in that: described CPU [1] is by central processor CPU, A/D converter U11, memory U10, PSD chip U4 forms, the AD0 of CPU～AD15 port by bus respectively with AD0～AD15 port of PSD chip U4, the D0 of memory U10～D7 port, A8～A14 port, the D0 of A/D converter U11～D7 port is connected, CPU /RD, / WR port meets the CNTL0 of PSD chip U4 respectively, the CNTL1 port, the WE of memory U10, the OE port, A/D converter U11 /WR, / RD port, the P1.5 port of CPU connects A/D converter U11's/the INT port, the HSO.1 of CPU～HSO.3 port connects harmonic elimination and output unit [3], the PG0 of PSD chip U4～PG7 port is by A0～A7 port of bus interface memory U10, PF0～PF7 port, PC0～PC4 port and PB0～PB4 port is respectively by bus interface man-machine interface unit [4], the PB6 of PSD chip U4, the PB7 port is the CS1 port of connected storage U10 respectively, A/D converter /the CS port, the CH0 of A/D converter U11～CH3 port connects 4 outputs of analog input unit [2] respectively.
3. voltage transformer ferro resonance diagnosis cancellation element according to claim 2, it is characterized in that: described analog input unit [2] is made up of four identical circuit, each circuit is made up of voltage transformer, transport and placing device again, respectively connection opening three angle voltages and A, B, C three-phase voltage of the input of voltage transformer wherein, the output termination transport and placing device of voltage transformer, transport and placing device and resistance, electric capacity are connected into the first-order filtering circuit, and the output of transport and placing device connects the signal input part of A/D converter.
4. according to the described voltage transformer ferro resonance diagnosis of claim 3 cancellation element, it is characterized in that: described harmonic elimination and output unit [3] are made up of inverter U2, solid-state relay U3, integrated alarm relay K A1, plant failure alarm relay KA2, three inputs of inverter U2 are connected with HSO.1～HSO.3 port of the CPU of CPU [1] respectively, and its three outputs are connected with VCC port, integrated alarm relay K A1 and the control coil of plant failure alarm relay KA2 of solid-state relay U3 respectively.
5. according to the described voltage transformer ferro resonance diagnosis of claim 4 cancellation element, it is characterized in that: described man-machine interface unit [4] is made up of display chip U16, key circuit, indicator light circuit, and the signal input part of display chip U16 is connected with PF0～PF7 port, the PC0～PC4 port of PSD chip U4 in the CPU [1]; Each key circuit is by button S1, resistance R 1, inverter U5 form, button be connected between power supply VCC and the ground after resistance is connected, its serial connection point connects the input of inverter, output is received the PB0～PB4 port of PSD chip U4 in the CPU [1] through bus, indicator light circuit is composed in series by LED 1, resistance R 6, a termination power VCC of sequential circuit, and the other end is through the U4PA1～PA7 port of bus interface PSD chip.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200420005829 CN2702502Y (en) | 2004-03-04 | 2004-03-04 | A ferromagnetic resonance diagnostic eliminator of voltage transformer |
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| Application Number | Priority Date | Filing Date | Title |
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| CN 200420005829 CN2702502Y (en) | 2004-03-04 | 2004-03-04 | A ferromagnetic resonance diagnostic eliminator of voltage transformer |
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| CN2702502Y true CN2702502Y (en) | 2005-05-25 |
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| CN 200420005829 Expired - Lifetime CN2702502Y (en) | 2004-03-04 | 2004-03-04 | A ferromagnetic resonance diagnostic eliminator of voltage transformer |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100373728C (en) * | 2005-11-21 | 2008-03-05 | 华北电力大学（北京） | Controllable damp device of ferromagnetic resonance for electromagnetic voltage transformer for distribution network |
| CN102097807A (en) * | 2011-01-24 | 2011-06-15 | 中国石油化工集团公司 | System for preventing power system from generating PT (potential transformer) ferromagnetic resonance |
| CN104237634A (en) * | 2014-08-14 | 2014-12-24 | 国家电网公司 | Device for diagnosing and eliminating power distribution network PT ferromagnetic resonance faults |
| CN104410070A (en) * | 2014-12-21 | 2015-03-11 | 国家电网公司 | Method for controlling frequent signal emission of microcomputer resonance eliminating device |
| CN104600688A (en) * | 2015-02-17 | 2015-05-06 | 安徽巨森电器有限公司 | Overvoltage suppression comprehensive device with GPRS (general packet radio service) wireless communication function |
| CN106549371A (en) * | 2016-11-09 | 2017-03-29 | 国家电网公司 | The method and apparatus for preventing PT ferromagnetic resonances from causing UFLS malfunction |
| CN108318762A (en) * | 2018-02-28 | 2018-07-24 | 南京南瑞继保电气有限公司 | The method of discrimination of voltage transformer power frequency ferromagnetic resonance |
| CN116706839A (en) * | 2023-06-08 | 2023-09-05 | 深圳瑞能电气设备有限公司 | Microcomputer electric power resonance diagnosis eliminating device and eliminating method thereof |
-
2004
- 2004-03-04 CN CN 200420005829 patent/CN2702502Y/en not_active Expired - Lifetime
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100373728C (en) * | 2005-11-21 | 2008-03-05 | 华北电力大学（北京） | Controllable damp device of ferromagnetic resonance for electromagnetic voltage transformer for distribution network |
| CN102097807A (en) * | 2011-01-24 | 2011-06-15 | 中国石油化工集团公司 | System for preventing power system from generating PT (potential transformer) ferromagnetic resonance |
| CN102097807B (en) * | 2011-01-24 | 2013-04-24 | 中国石油化工集团公司 | System for preventing power system from generating PT (potential transformer) ferromagnetic resonance |
| CN104237634A (en) * | 2014-08-14 | 2014-12-24 | 国家电网公司 | Device for diagnosing and eliminating power distribution network PT ferromagnetic resonance faults |
| CN104237634B (en) * | 2014-08-14 | 2018-03-06 | 国家电网公司 | Power distribution network PT ferro resonance failure diagnosis and cancellation element |
| CN104410070A (en) * | 2014-12-21 | 2015-03-11 | 国家电网公司 | Method for controlling frequent signal emission of microcomputer resonance eliminating device |
| CN104600688A (en) * | 2015-02-17 | 2015-05-06 | 安徽巨森电器有限公司 | Overvoltage suppression comprehensive device with GPRS (general packet radio service) wireless communication function |
| CN106549371A (en) * | 2016-11-09 | 2017-03-29 | 国家电网公司 | The method and apparatus for preventing PT ferromagnetic resonances from causing UFLS malfunction |
| CN108318762A (en) * | 2018-02-28 | 2018-07-24 | 南京南瑞继保电气有限公司 | The method of discrimination of voltage transformer power frequency ferromagnetic resonance |
| CN108318762B (en) * | 2018-02-28 | 2020-09-08 | 南京南瑞继保电气有限公司 | Method for judging power frequency ferromagnetic resonance of voltage transformer |
| CN116706839A (en) * | 2023-06-08 | 2023-09-05 | 深圳瑞能电气设备有限公司 | Microcomputer electric power resonance diagnosis eliminating device and eliminating method thereof |
| CN116706839B (en) * | 2023-06-08 | 2024-02-06 | 深圳瑞能电气设备有限公司 | Microcomputer electric power resonance diagnosis eliminating device and eliminating method thereof |
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Expiration termination date: 20140304 Granted publication date: 20050525 |